Satellites from Amazon’s planned internet megaconstellation are bright enough to interfere with astronomical observations, according to a new study, adding to growing concerns over the impact of satellite swarms on humanity’s view of the universe.
The study, posted on the preprint platform arXiv on January 12 and yet to undergo peer review, analyzed nearly 2,000 observations of Amazon’s low Earth orbit (LEO) satellites, previously known as Project Kuiper. Researchers found that the satellites exceed brightness limits recommended by the International Astronomical Union (IAU), which are meant to allow satellite networks and astronomical research to coexist.
Amazon’s internet satellites are “troublesome’
Amazon’s satellites orbit at around 391 miles (630 kilometers) above Earth and have an average apparent magnitude of 6.28. While generally too faint for casual stargazers, the satellites are still bright enough to disrupt sensitive telescopic observations. In about 25% of recorded observations, the satellites were visible without the aid of telescopes.
“Bright satellites are particularly troublesome for large-scale astronomical surveys conducted at ground-based observatories like the Vera C. Rubin Observatory,” said study lead author Anthony Mallama of the IAU Center for Protection of the Dark and Quiet Sky. He added that satellite glare can also affect space-based instruments such as the Hubble Space Telescope.
Mallama and his colleagues have previously studied other satellite networks, including SpaceX’s Starlink constellation, which currently dominates low Earth orbit with around 9,500 satellites. They have also examined AST SpaceMobile’s massive BlueBird satellites, whose large antennas make them the brightest artificial objects in the night sky.
Compared with these systems, Amazon’s satellites are dimmer than the BlueBird satellites and slightly fainter than most Starlink spacecraft. However, Mallama noted that Starlink satellites spend much of their orbits in Earth’s shadow, reducing their visibility. Amazon’s future satellites are expected to orbit at lower altitudes of about 366 miles (590 kilometers), a change that could make them brighter.
Working with astronomers
Satellite operators, including Amazon and SpaceX, say they are working with astronomers to reduce satellite brightness. Proposed measures include modifying spacecraft surfaces to reflect sunlight away from Earth and adjusting satellite orientation to limit visibility from the ground.
John Barentine, an astronomer who studies satellite impacts on astronomy, said Amazon has shown progress since launching its first test satellites in 2023. “Amazon Leo is an instance where the operator engaged with astronomers early in the design phase,” he said, calling the results “encouraging.”
Alarm over satellite megaconstellations began in 2019, shortly after SpaceX launched its first Starlink satellites, when astronomers reported telescope images streaked by passing spacecraft. While mitigation efforts have improved satellite designs, a November 2025 study by Mallama and colleagues found that nearly all active internet satellite constellations still exceed IAU brightness limits. The exception was OneWeb, which operates at much higher altitudes.
Astronomers warn that without stronger safeguards, the rapid growth of satellite constellations could permanently alter ground- and space-based observations of the cosmos.